On the fatigue life prediction of single-lap composite bolted joints

Abstract

Improving the numerical techniques to foretell the fatigue life of composite joints is a crucial work. The main goal of this study is to present a new algorithm for simulating the fatigue behavior of composite laminates. This algorithm was applied to the composite bolted joints and the effects of bolt arrangement and laminate configuration was considered. The fatigue life of defined layers was estimated by Hashin’s failure criteria. In contrast to the previous investigations, the influences of load ratio on fatigue curves were determined using Kawai’s rule. Also, negative mean stresses were considered using the constant life diagrams. The damage parameter was estimated by a modified form of Miner’s rule. To validate the proposed model, numbers of specimens were fabricated with [0/45/−45/90]s and [0/90/0/90]s lay-up. For each configuration, the samples were joined by two and four bolts. The fatigue life predictions of all configurations were compared with the experimental data and good agreement was observed.